Electromagnet.



PATENTED NOV. 24, 1903.

D. L. LINDQUIST. ELEGTROMAGNET.

APPLICATION FILED JULY 14, 1903.

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No. 744,773. PATENTED NOV. 24,1903.

' D. L. LINDQUIST. ELEOTROMAGNET.

APPLICATION FILED JULY 14, 1903.

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WITNESSES: g INVENTOR 1% 0% WM M Q, 1 BY T a; Z] ATTORNEY UNITED STATESPatented Novembe1i24, 1903.

DAVID LEONARD LINDQUIST, OF YONKERS, NEW YORK.

ELECTRDMA GNET.

SPECIFICATION g pa o e s Pa No. 744,773, dated November 24, 1903.

Application filed July M, 1903. Serial No. 165,428. (No model.)

To all whom, it may concern:

Be it known that 1, DAVID LEONARD LIND- QUIST, of Yonkers, Westchestercounty, New York, have invented a new and useful Improvement inElectromagnets, of which the following is a specification.

The invention relates to an electromagnet constructed to be energized byan alternating current and when so energized to attract its armature andhold the same in position by a substantially constant pull and withoutchat tering.

The invention consists in an electromagnet having a plurality of coilssymmetrically disposed around a central axis, the individual axis ofeach of said coils being parallel to said central axis; also, in theconstruction more particularly hereinafter set forth.

In the accompanying drawings, Figure 1 is a side elevation of my magnetand its armature, showing three of the six coils present, the middlecoil being in vertical section. Fig. 2 is a vertical section on the lineas at of Fig. 1. Fig. 3 is atop view. Fig. 4 is a diagram incross-section on the line 1 g] of Fig. 2, showing the connections of themagnet represented in Figs. 1, 2, and 3 for three-phase currents. Figs.5, 6, and 7 illustrate modified forms and and diiferent windings.

Similar letters and numbers of reference indicate like parts.

The magnet A is constructed as follows: 1 is a supporting-ring carriedby standards 2. The inner periphery of said ring is threaded to receivethe inverted-cup-shaped support 3, integral with which is a centralsleeve 1. The outer periphery of ring 1 has a downwardlyturned flange 6.On the exterior of support 3 and held between said piece and flange 6 isthe laminated magnet-core 7, the laminations being concentric with saidsupport 3. The laminated core 7 and support 3 are cut away at theirlower portion to form six equidistantly-spaced pole-pieces 1 1 15 16 1718 19, and upon each of said pole-pieces is wound a coil 8 9 10 11 1213. Said coils fit securely upon said pole-pieces and extend below thesame, so that each pole-piece fills about onehalf the cylindrical spacewithin its associated coil. The several coils are alike, and their axesare all parallel to and symmetrically disposed around the axis of thecylindrical laminated core 7.

The armature 13 consists of a ring 20, similar to ring 1 and providedwith a flange 21. The inner periphery of ring 20 is threaded to receivethe cylindrical cup-shaped support 22, on the exterior of which is thelaminated cylinder 23, held between flange 21 and the said support 22.The laminated cylinder 23 is of the same thickness as the magnet-coreand, with its support 23, is cut away at its upper portion to form sixpole-pieces 24, each of which is so located and of such size as that allof said pole-pieces may loosely enter the magnetcoils 8 to 13 and tillthe spaces therein not already filled by the pole-pieces 14 to 19. Thesupport 23 has a central sleeve 25 internally threaded to receive thethreaded rod 26. Said rod extends loosely through the sleeve 4 ofmagnet-support 3, and at its upperend carries the bell-shaped stop 27.In the upper side of ring 1 is a dovetail groove containing a cushion28, ofrubber or leather, which forms an elastic seat for the edge ofstop 27. .On rod 26, below support 28, is a nut 29.

When the magnet A is not energized, armature B drops into the positionshown in Fig. 1, the stop 27 then resting on the elastic cushion 28.hen, however, magnetA is excited, the coils draw into themselves thepole-pieces 24: of the armature, thus raising said armature to theposition shown in Fig. 2. The extent of movement of the armature may belimited as desired by means of the nut 29.

The winding of the magnet having six polepieces, as above described, isindicated in Fig. 6, in which a, b, and 0 represent conductors ofcurrents of difierent phase. Instead of constructing magnet and armaturewith six pole-pieces I may use a different number. Thus in Fig. 5 threeand in Figs. 6 and 7 four pole-pieces are illustrated. The conductors ab c in Fig. 5 are wound for three-phase current and in Fig. 6 fortwophase current. Fig.7 shows a magnet similar to that of Fig. 6 adaptedto a singlephase-current system, an ohmic resistance 0 being placed inbranch to get phase difference in the two branches of the winding and soto obtain the desired approximately constant pull. In all cases it willbe noted that the axes of the coils are always parallel to andsymmetrically disposed around the axis of the cylindrical magnet-core.

I claim 1. An electromagnet having a plurality of coils symmetricallydisposed around a central axis, the individual axis of each of saidcoils being parallel to said central axis, and means for producingcurrents of different phase in said coils.

2. An electromagnet having a cylindrical core and a plurality ofsymmetrically-disposed coils thereon, the said coils having theirindividual axes parallel to the axis of said core, and means forproducing currents of different phase in said coils.

3. An electromagnet having a cylindrical core,withsymmetrically-disposed pole-pieces at one end thereof, coils on saidpole-pieces and means for producing currents of different phase in saidcoils.

4. An electromagnet having a cylindrical laminated core With integralsymmetricallydisposed pole-pieces at one end thereof, coils on saidpole-pieces and means for producing currents of different phase in saidcoils.

5. An electromagnet having a cylindrical core withsymmetrically-disposed pole-pieces at one end thereof and coils on saidpolepieces and extending beyond the same.

6. In combination With an electromagnet having a plurality of coilssymmetrically disposed around a central axis, the individual axis ofeach of said coils being parallel to said central axis, a movablearmature having pole-pieces corresponding in number and position to saidcoils.

7. In combination with an electromagnet having a plurality of coilssymmetrically disposed around a central axis, the individual axis ofeach of said coils being parallel to said central. axis, a movablearmature having pole-pieces corresponding in number and position to saidcoils and means for regulating the extent of movement of said armature.

8. In combination With an electromagnet having a cylindrical core withsymmetrically-disposedpole-pieces at one end thereof and coils on saidpole-pieces extending beyond the same, a movable armature havingpole-pieces correspondingin number and position to said coils andconstructed to enter the same.

9. The combination with the cnpshaped cylindrical support of thelaminated core on said support provided With integralsymmetrically-disposed pole-pieces and coils on said pole-pieces.

10. The combination With magnetA. having a cup-shaped cylindricalsupport and laminated core thereon provided With integralsymmetrically-disposed pole-pieces, and coils on said pole-pieces, ofthe movable armature B having a cup-shaped cylindrical support andlaminated core thereon provided With integral symmetrically-disposedpole-pieces constructed to enter said coils.

11. A cylindrical electromagnet having a plurality of symmetricallydisposed polepieces and coils thereon, a cylindrical armature havingaplurality of symmetrically-disposed pole-pieces constructed to entersaid coils, a central supporting-rod for said armature extending axiallythrough said magnet and a stop on said rod constructed to bear on theouter end of said magnet and limit the stroke of said armature.

12. A cylindrical electromagnet having a plurality of symmetricallydisposed polepieces and coils thereon, a cylindrical armature havingaplurality of symmetrically-disposed pole-pieces constructed to entersaid coils, a central supporting-rod for said armature extending axiallythrough said magnet and a stop on said rod constructed to bear on theouter end of said magnet and limit the stroke of said armature, andmeans for ad justing the distance of said stop from said magnet end.

13. A cylindrical electromagnet having a plurality of symmetricallydisposed polepieces and coils thereon, a cylindrical armature havingaplurality of symmetrically-disposed pole-pieces constructed to entersaid coils, a central supporting-rod for-said armature extending axiallythrough said magnet and a stop on said rod constructed to bear on theouter end of said magnet and limit the stroke of said armature and onsaid magnet end, an elastic seat for said step.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing Witnesses.

DAVID LEONARD LINDQUIS'I.

Witnesses:

W M. II. SIEGMAN, I. A. VAN W ART.

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